The massive integration of distributed generation (DG) of power is leading to important changes in the operation of distribution networks. In this context, the protection schemes are experiencing major transformations. Traditionally, fault detection together with the associated relaying schemes and fault location functionalities have been considered as separate processes since the latter usually requires computational efforts that do not fit the time latencies needed by the protections. Along the years, several fault detection and location methods have been proposed for distribution networks. The majority of them are based on impedance measurements, traveling waves or phasor measurements. However, the literature only discusses the possibility of merging the detection and location functionalities. Recent publications have discussed the use of phasor measurement units (PMUs) to develop low-latency and high-refresh rate real-time state estimators (SEs) for distribution networks. The use of low-cost hardware platforms is contributing to the massive use of PMUs in distribution networks. Dedicated installations in real distribution networks have demonstrated the feasibility of this solution. As an example, the active distribution network (ADN) can be equipped with PMUs in every bus measuring nodal voltages and injected current synchrophasors. By leveraging the distribution network operator need for real-time monitoring, other applications, such as fault detection and location, might be developed using this same metering infrastructure.
On the other hand, in transmission networks, PMU-based infrastructures have been a reality for many years now. The existing infrastructures can be upgraded to meet the requirements of real-time fault detection and location, especially in specific and limited portions of the power grid.
The conventional fault location methods currently employed in transmission networks can be classified into two major categories:
(1) Methods based on the fundamental frequency components of voltage and current signals, and
(2) Methods exploiting the characteristics of the fault-generated traveling waves. However, despite all the advancements in the field of fault location methods and systems for power grids, further improvements and solutions are necessary and required.